[Induction of lipid peroxidation and change of fatty acid composition in rats fed methylmercury].

Four groups of rats, with 5 animals in each, were fed a diet to which 1, 2, 4 or 8 ppm of methylmercury (MeHg) were added while another group of 5 rats was fed a diet containing no MeHg as a control. Moreover, each rat was daily supplied the same volume of these diets. During the experimental period of 40 days, body weights of the rats were daily checked individually. On day 40, expired air of the rats was collected to analyse for ethane and pentane production, and then the rats were sacrificed to obtain the liver, kidneys, brain and plasma. Thio-barbituric acid (TBA)-reactants in the selective organs and plasma were measured to investigate the effects of MeHg on lipid peroxidation. Further, gas-chromatographic analyses of fatty acids were carried out on the samples of the selective organs and plasma to examine the effects of MeHg on lipid metabolism. Results obtained were as follows: 1. The fifth day after the experiment started, the growth rates of the groups fed a diet containing MeHg (the MeHg groups) were higher than those of the control group. Moreover, the growth rates tended to increase with increases of MeHg concentrations in food from days 25 to 32 of the experimental period. Furthermore, the weights of the kidneys increased with increases in MeHg concentrations in food. 2. The amounts of expired ethane and pentane did not increase proportionally with increases in MeHg concentrations in food but those of expired ethane and pentane were higher in the MeHg groups than in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)